Three explosions have been reported in the city, and at least 34 people are reported dead. Isis has reportedly taken credit for the attacks.

"Explosions at Brussels airport; Apple: national security is more important than privacy," tweeted Khosla, linking to a Los Angeles Times article about the attacks, apparently referring to Apple CEO Tim Cook's refusal to hack an iPhone belonging to the perpetrator of a mass shooting in December in San Bernadino in California.

"Yep, when Apple finally gives us all OPM-level privacy, we'll finally get our national security back," he tweeted. "Entrepreneurs: if your startup makes us more secure via less privacy, I've found an investor for you!"

"Look, all the government is asking for is public access to the sandy beach that is your data. Privacy is so greedy," he continued, apparently referring to Khosla's dispute with California's State Lands Commission over a strip of beach property in Half Moon Bay.

Look, all the government is asking for is public access to the sandy beach that is your data. Privacy is so greedy. https://t.co/DP75ndFtva

Rivera said in a direct message over Twitter: "I wouldn't expect his one tweet to have broad implications, but I think it's just a sign he might be out of touch with the issues involved here. And I say might, because this is Twitter, where context is always missing. Perhaps in the most generous interpretation of his tweet, there's a point I could (mostly?) agree with."